how to stop Windows rebooting after an auto update

I'm a snob and I am unbearable company because I'm a fully paid up member of the Mac brigade. Every day there is at least one moment of pleasurable reflection when I appreciate something on one of my Mac devices where I'm glad they paid a great deal of attention to the detail.
Windows on the other hand...
No actually I'm not dead against Microsoft or Windows as it's definitely horses for courses and no giant corporation can be right all the time. But I do have my pet hates. Here is one.

You leave your windows machine for a coffee break. The Visual Studio windows are arranged. Source files open at specific points as you struggle your way through more diagnostics.

You come back and Windows has rebooted!
Who in the name of ... thought that would be a neat thing to do.

Yes I'm sure from an OS perspective, a Microsoft perspective, from a Paternalistic systems perspective they're doing it for our own good.

I hear that Windows 8 will require fewer reboots. That makes me smile.

So, how to disable this patronising annoyance:

Step 1
Go to the Start button, or whatever it's called these days, and in the search box type

gpedit.msc

this opens the Group Policy editor.

Step 2
In the tree view,  navigate to:

Computer Configuration -> Administrative Templates -> Windows Components -> Windows Updates

Step 3
In the right hand pane:
Double-click on:

 "No auto-restart with logged on users for scheduled automatic updates installations"

Step 4

Set this to Enabled.
Click OK to go on your merry way.